# def fac(n):
#     if n <= 1:
#         return 1
#     else:
#         return n * fac(n - 1)
#
#
# num = int(input('请输入一个正整数：'))
# s = fac(num)
# print(num, '的阶乘是: ', s)
#
#
#
# def su(n):
#     if n == 1:
#         return 1
#     else:
#         return n + su(n-1)
# print(su(120))


# 计算斐波那契数列
# def fibo(n):
#     if n <= 2:
#         return 1
#     else:
#         return fibo(n - 1) + fibo(n - 2)



# 使用ym函数
# sum = lambda a,b,c: a+b+c
# print(sum(1,2,3))
#
#
# # 编写lambda函数
# fun = lambda m: m*m
# print(fun(5))